1. Field of the Invention
The present invention relates to an image pickup apparatus comprising an image extracting unit and particularly to an image pickup apparatus for performing an image extraction process and automatic feedback control of white balance.
2. Description of the Related Art
Regarding the image extraction process, Japanese Patent Application Laid-Open No. 225328/1994, which corresponds to U.S. Pat. No. 5,412,487, describes the stable extraction of an object, depending on the extracting condition on a standardized color difference plane, by standardizing a color difference signal with a luminance signal.
In regard to automatic white balance control, Japanese Patent Application Laid-Open No. 344530/1993 describes performance of automatic white balance control with higher accuracy by utilizing an intelligent algorithm recognizing the image pickup environment.
However, the feedback type automatic white balance control generates a malfunction by erroneously judging as white a color approximated to an achromatic color when a small amount of white is included in an image, resulting in change of a degree of color saturation and hue of the image picked up. As a result, it becomes difficult in the image extraction process for extracting an object on the standardized color difference plane to extract the object with high accuracy due to a change of distribution of the object on the standardized color difference plane.